261641237 has 36 divisors (see below), whose sum is σ = 328995936. Its totient is φ = 206219520.

The previous prime is 261641179. The next prime is 261641249. The reversal of 261641237 is 732146162.

It is not a de Polignac number, because 261641237 - 2¹⁰ = 261640213 is a prime.

It is a super-2 number, since 2×261641237² = 136912273797780338, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (261641287) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 537008 + ... + 537494.

It is an arithmetic number, because the mean of its divisors is an integer number (9138776).

Almost surely, 2^261641237 is an apocalyptic number.

It is an amenable number.

261641237 is a deficient number, since it is larger than the sum of its proper divisors (67354699).

261641237 is a wasteful number, since it uses less digits than its factorization.

261641237 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 558 (or 528 counting only the distinct ones).

The product of its digits is 12096, while the sum is 32.

The square root of 261641237 is about 16175.3280337680. The cubic root of 261641237 is about 639.5905885763.

Adding to 261641237 its reverse (732146162), we get a palindrome (993787399).

The spelling of 261641237 in words is "two hundred sixty-one million, six hundred forty-one thousand, two hundred thirty-seven".